Optimization of the preparation of fungal-algal pellets for use in the remediation of arsenic-contaminated water

This study was conducted to optimize the preparation of fungal-algal pellets for use in the removal of arsenite (As(III)) and arsenate (As(V)) from water. Three parameters, i.e., glucose concentration, shaking speed, and pH, were investigated to show their effects on the immobilization efficiency of algal biomass attached to fungal mycelial pellets. The highest immobilization efficiency was achieved at 5 g glucose L-1, 140 rpm, and pH 7. Furthermore, the fungal-algal pellets with different initial algal biomass were tested regarding the stability and their capability of removing As(III) and As(V). The fungal-algal pellets could not keep good stability when the initial algal biomass was more than 4.8 x 10(7)cells mL(-1). The highest removal rates of As(III) and As(V) were obtained by the fungal-algal pellets with initial algal biomass of 4.8 x 10(7)cells mL(-1), and the removal rate of As(V) was much higher compared with that of As(III). Similar trends were observed for the concentrations of total arsenic as well as As(III) and As(V) in fungal-algal pellets. The fungal-algal pellets with initial algal biomass of 4.8 x 10(7)cells mL(-1)showed a significant potential for removing As(V) from water, and microalgae might play a key role in the absorption and transformation of inorganic arsenic. Adsorption kinetics studies suggested that the adsorption of As(V) onto fungal-algal pellets followed the pseudo-second-order kinetic model, and the pseudo-first-order kinetic model was more appropriate for describing the adsorption of As(III).